Electric-weld-forging mat



Dec. 18 1923.

l. W. HENRY ELECTRIC WELD FORGING MAT Original Filed Aug. 4, 1921 A wnbeutoz 1 a z Patented Dec. 18, 1923.

UNITED STATES PATENT OFFICE.

IRA W. HENRY, OF NEW YORK, N. Y., ASSIGNOR, BY DIRECT AND MESNE ASSIGN-MENTS, TO THE ELECTRIC FORGE CORPORATION,

TION OF DELAWARE.

or NEW YORK, N. Y., A CORPORA- ELECTRIC-WELD-FORGING MAT.

Original application filed August 4, 1921, Serial No.

1922. Serial No. 542,905.

To all whom it may concern:

Be it known that I, IRA W. HENRY, citizen of the United States, andresident of New York city, in the county of New York and State of NewYork, have invented certain new and useful Improvements inElectric-Weld-Forging Mats, of which the following is a specification.

This invention relates to an electric weldforging mat. I call the mat anelectricforging mat because the jointing effected is effectedsuccessively under pressure together of the fused surfaces to be united.The objects of the invention are to electrically weld under pressure,metallic surfaces together by the heat of an electric current withmarked economy and with a practical result, to wit; a joint which, forlarge opposed surfaces, heretofore only imperfectly or partially weldedby known electric welding processes, is of already demonstrated seemingperfection, in that the welded joints under tests have been proven to bestronger than'the body of the metal Welded, in respect to tensilestrength; and to be welded together at all points of the opposed weldedsurfaces.

This application is a division of my United States application SerialNo. 489,- 869, filed August 4, 1921, and allowed Jan. 25, 1922. The matherein shown is also shown in my application, Serial No. 499,87 9, filedSeptember 12, 1921, and allowed Feb. 14, 1922.

My new mat is adapted for use in structural iron work as a substitutefor riveting and bolting beams, plates and the like together inship-building operations, the erection of buildings, the building ofbridges and tunnels, pipe lines, welding of broken shafts, etc., allwith a great saving of labor, together with a reduction of weight andeconomy of current.

My mat may be used with either alternating current or with directcurrent apparatus.

The hereinafter described angle irons are merely typical of beams,girders, plates, pipes, flanges, etc., that are to be jointed by use ofmy new mat which of and by itself constitutes a new article ofmanufacture that may be made in small pieces of any desired areas, butis preferably manufactured in long pieces, from which portions 489,869.Divided and this application filed March 11, Renewed November 23, 1922.

of required areas are cut off by the workmen for use in situ.

In. the accompanying drawings illustrating the principle.ofthisinvention and. the.

best mode now known to me of applying that principle,

Fig. 1 is a side view, and

Fig. 2 an end view of angle irons having opposed flanges to be jointed,and showing a. welding mat interposed between the flanges; Fig. 1 alsoillustrating a power clamp applied to the flanges, and both figuresindicate details of electric circuit connections.

Fig. 3 is a side elevation, and

Fig. 4 is an end elevation of the weldin mat.

Referring to that form of the invention shown in the drawings, 1indicates opposed angle iron flanges that are to be jointed together bythe heating effect of an electric current with simultaneous pressure andby use of the welding mat, which is indicated by M. This mat comprises,in the form shown, a plurality, five as shown, of wires which areelectric conductors, and which are spaced apart one from another inparallelism. These wires, from one edge portion to the opposite edgeportion of the mat, decrease in diameter. Thus, as shown in Fig. 4, oneedge wire 2 is of larger diameter than the next wire 3, which is oflarger diameter than the next wire 4:, which is of larger diameter thanthe next wire. 5, which is of larger diameter than the other edge wire6. In practice, I find that No. 6 B 8; S gauge is a good size for thelargest wire, and that No. 18 B & S gauge is a good size for thesmallest wire, the intermediate wires varying decreasingly in diameter.It is noted that the electrical resistance of these wires corresponds totheir respective cross-sectional areas. The wires are held apart andtied together by any suitable means, such, for example, as a piece ofwire netting 7'; such netting being also an electrical conductor andbeing meltable together with. the wires 8 which tie the wires 2 to 6 tothe netting. The conductor wires 2 to 6 are also meltableand the entiremat is melted into the joint formed by the present method. The mat isshown loaded or coated with a suitable flux 9, borax, for example. whichis preferably fused in place as a portion of the tcriorly of each copperplate an insulating plate 11 is located and the terminals 12 for theelectric current are attached to the copper plates, or electrodes. Thesecopper plates or electrodes are preferably provided with interior spacedapart water passages 10, one communicating with the other through aconduit connection 10 When in use, water may be admitted into the openend of one of the passages and allowed to escape through the open end ofthe other passage, as indicated by arrows in Fig.2. The purpose ofpassing water through these electrodes 10 is to reduce their temperaturewhen they are in use and become highly heated by the electric currentpassin through them.

When the current is established the circuit,

of course, will be through the copper plates and the flanges 1 to andthrough the element of the mat having the largest diameter; for example,through the largest wire 2 of the mat which spaces the flangesapart,like a wedge, until it has become sufficiently melted to permitthe flanges to contact with the next largest wire 3, which then servesto space the flanges apart until it becomes sufliciently melt-ed topermit the next largest wire t to act as the effective spacer, and soon, through all the series 13f conducting wires comprised in the mat.uring such action and the transformation of the mat, the flanges areunder some kind of mechanical pressure whereb they are successivelyforced together, and l have shown, merely as illustrative of anysuitable power device for the purpose, the heads 13 of hydraulic tongsapplied to opposite sides of the assembled flanges, mat, copper orconducting plates and insulating plates, the arms 14 of the tongs beingadapted to be pushed apart at their outer ends by ressure in a hydrauliccyl inder construction 15, the tong arms 1 1 being pivoted together attheir crossing 16, and their outer ends being respectively pivoted at 17to a piston rod 18, each carrying a piston 19 within the cylinder forwhich a central water supply pipe 20 is provided for forcing the twopistons apart at the proper time and thereby compress the headsoppcsedly against the insulating plates 11. lifhe tong arms 14, whichare, of course, of metal, span the assembled arts and are out of contactwith them, and y the use of the insulating plates 11 the powerapplication. device is kept out of electrical connection witl'; theassemblage of conductors, flan es mat. The welding operation is easiestamazes When the flanges are under pressure, a practically gas tightjoint is formed between the contacting walls of the flanges, initiallywith the largest wire or conductor 2; and as, initially, the opposedsurfaces of the flanges do not bind on the smaller wires, such as 3,4, 5and 6, so as to form gas tight joints all gases generated by the fusingof the surfaces of the flanges and of the conductor 2, and of the flux,must travel downwardly in the direction of the vertical arrow shown inFig. 2. The gas tight joint referred to is an important feature of thisinvention.

During the successive melting of the flux and metallic elements of themat, gases are generated and they escape downwardly with force and areeffective for blowing out, to a greater or less'extent, the usual scale,dirt, etc., on the generally more or less oxidized opposed surfaces ofthe flanges, and thereby clean the surfaces to be united. Suchgeneration, control and escape of the gases, which are of very hightemperature, is a feature of the present invention, although an incidentof the use of the successively consumable mat which, in whole and inpart,

disappears by being merged with and molec- "are under pressure onetowards another the area of contact largely increases. This conditionapplies successively to the remainder of the mat as the diameters of itsconductors 3, i, 5 and 6, for example, are successively reduced. Forthis reason a current of very high amperage at low voltage may be usedwithout formation of an arc; and as each conductor of the mat issuccessively heated and flattened its resistance increases with the heatas it is fused. The electric current carrying capacity of thesuccessively heated, melted and flattened surfaces of the conductors issuccessively established b the pressure of the flanges and when theconductor of the least diameter has been fused the weld or is completed.This successive under pressure, which l consider to in the nature ofelectric-forging, results in a substantial saving of current and also inpractically and wholly, according to the experiments which l havehitherto con ducted, welding every part of the opposed flanges.Moreover, when, in the prior art, surfaces of any considerable area arein complete, or approximately complete physical contact under pressure,and an electric weldin applied, as in the welding broken shafts and inthe welding of plates, beams, girders, etc., buckling results and suchbuckling is one of the great disadvantages attending electric weldingoperations on all but relatively small opposed surfaces by prior artmethods. Such buckling is occasioned because the welding current instriving to establish a circuit through a point or points of leastresistance unequally heats the surfaces at various parts or points, withthe result that the unequal heating causes the metal to bend, warp orbuckle. By my invention. in consequence of the successive and relativelysmall areas of the heating and melting of the surfaces during theprogress of the welding operation, the highly objectionable buckling ofthe prior art is minimized and in some cases elimi-' nated.

What I claim is:

1. As a newv article" of manufacture. the herein described welding matcomprising a plurality of spaced apart, fusible, electric metallicconductors having cross-sectional areas of successively reducedcross-section from one portion of the mat to another portion; and meansfor holding the conductors in mat form.

2. As a new article of manufacture, the herein described welding matcomprising a plurality of spaced apart, fusible, electric, metallicconductors having cross-sectional areas of successively reducedcross-sections from one portion of the mat to another portion; means forholding the conductors in mat form; and a flux fused in place on themat.

3. The combination, in a Weld-forging operation, with a weld-forgingapparatus comprising means for pressing parts to be welded one towardsthe other of opposed parts to be welded and having located between thema welding mat comprising a plurality of spaced apart, fusible, electricmetallic conductors having cross-sectional areas of successively reducedcross-section from one portion of the mat to another portion and fusiblemeans for holding the conductors in mat form; the conductors of largercrosssectional dimension successively forming, when fused with the partsto be welded, a gas tight joint, each joint serving to compel gasesgenerated from the fusion to travel away from the joint outwardly frombe tween the parts to be welded.

Signed at New York city, in the county of New York and State of NewYork, this 7th day of March A. D. 1922.

IRA W. HENRY.

